Plastered concrete ceiling and method of making same.



M. Y. SEATO-N'& 3. s. HARRIS.

PLASTERED CONCRETE CEILING AND-'METHOD OF MAKING SAME.

' 'APPLICATION FILED MAR. 23. 1911.

1,300,498. Patented Apr. 15, 1919.

"UNITED sTAtrEs PATENT OFFICE.

MAX Y. sEA'roN AND JOHN.S.--HARRIS,-OF CLEVELAND, OHIO, Assr'eNoRs TO THE ARGO COMPANY, or CLEVELAND, 01110, A CORPORATION or onro.

PLASTERED CONCRETE CEILING AND METHOD 9F MAKING SAME.

To all whom it may concern: k

Be it known that we, MAX Y. SEATON and JOHN S. HARRI's,-citizens of the .United States, and residents of .Cleveland, county of Cuyahoga, State of Ohio, have jointly invented a 'newand useful Improvement in Plastered Concrete Ceilings and Methods of Making Same, of which the following 1s a specification, the principle of the invention being herein explained and the best mode in-' which we have contemplated applying that principle, so as to distinguish it from other inventions. i s

The present invention, relating as indicated to a plastered concrete ceiling and method of making same, has more particular regard to the application of a'plaster coat to a'concrete surface by the use of an intermediate binder of a cementitious substance, which will produce a composite structure of considerable strength, and one which will not fail even under the most adverse conditions. To the accomplishment of the foregoing and related ends, said invention, then, consists of the means hereinafter fully described in the claims.

The annexed drawing and the following description set forth in detail one 'method and one product exemplifying our invention, such disclosed procedure and product constituting however, but one of various applications of the principleslof our invention.

In said annexed drawingz and particularly pointed out The single figure there appearing is a cross-sectional view illustrating a cellmg constructed in accordance with the principles of our invention. 7

Considerable difliculty has been the application of plaster to concrete sur-- faces, and in particular to the application of plaster to concrete ceilings where the. weight of the plaster must be held by the bond between the plaster and the concrete.

It is customary to first apply a thili'coating of a heavy bituminous paint to thecoilcrete surface and to then apply the plaster coats againstthis painted surface, but this metlfo'd is unsatisfactory, and is not permanent, the

plaster often falling ofl after only a. very few years of use. The bonding efliciency of such a paint is low however and its chief advantage is obviating the wetting down of the walls which must be done if plaster ap-.

found in of-this substance to a concrete surface is 'by Specification of Letters Patent. Patented Apr, 15, 1919 Application filed March 23, 1917? Serial No. 156,898.

plied direct. In some cases sand is blown against and into this paint .toroughen-its surface and increase its effectiveness as a bond but even this step does not render the materlal satisfactory. The only method there is mixed a considerable quantity of fibrous material, such as asbestos or a silky silicate to increase 1ts body. "Var1ous oils oil, soy-bean oil, or in fact any good drying oil. These oils are first treated by Inethods known to. varnish makers to -11'1cr ase, I their viscosity and a large amount of sh rt 1 asbestos fiberis then mixed withtheoil to increase its strength. It is essential that this substance be inertin the presence of alkalis and'insoluble in water since both alkalis and water are found to some extent in the concrete' against which this substance is applied and in the plaster which subse quently applied to the partially dried sub- 1 stance. The oil when treated may of course be thinned with suitable agents such as tur-.

pentine oriturpentine substituteuntil it is sufliciently plastic for working and spread-v The preferred method of the application troweling the same over the surface to a thickness of from betweeuone sixteehth and one thirty-second of an inch, which is about the least thickness which a mason can conveniently apply the material by means of a trowel. At this thickness 25 pounds of the material will cover about 100 square feet of surface, althoughwe have found that good results can still be obtained by theapplication of the substance in "various amounts 1 w After the viscous oil has been applied to the concrete thefirst plaster coat is applied before the bonding-substance is thoroughly may be used, such as china-wood oil, linseed 1 her of plaster coats I. used, as it '-that very dltion 0 7 ished coat of plaster may to the ce'mentitious substance.

finish of a standard comand the best results are ing the plaster within one obtained 'by applyhour after the -oil 'has been applied. One, two or even more coats of plaster may tomary in plastering practice under be applied, as is cusdifferent conditions and the bond between the plaster and the pend upon the strength tween the first plaster coat, cementitious or bonding substance concrete.

concrete will of course deof the union, be-

the intermediate and the The strength of the ceiling formed accordance with our invention depends to some extent upon the composition of the plaster,

but even with the weakest form of plaster ordinarily used, sisting of four parts of plaster of Paris,

which is a white finish conv lime to one part of an excellent bond is obtained between the plaster and concrete and a ceiling of satisfactory strength is obtained. the figure in the drawing, there is shown .a concrete Referring to which has been applied bonding substance 2.

ceiling 1 upon a coating of our Upon the latter is the first or scratch coat of plaster 3 and on this plaster the final coat may 4. Obviously the nun}- be varled to su1tthe conditions and finish required. A brown coat (the coat 3) is ordinarily used where the surface of the concrete is so. rough, due to form marks, alr pockets. and p101e0t111g' lumps of aggregate that does not serve to case a brown coat is necessary we by using the bonding coat give a smooth surface. In

have found satisfactory results are obtained a mixture of four 46 sand to one part of hard wall or five parts of plaster, or

psum laster, preferably also withthe adhair- Tlus mixture is then, of

course, brought to a workable condition by the addition of a. suitable .In the brown coat hme may for a part of the hard wall the use of lime the plaster, only a small is desirable that amount of water. be substituted laster, but as diminishes t e strength of amount should be coat have considerable structural strength. If the concrete has a sufliciently smooth 7 surface so that when the bonding substance is applied thereover a relatively smooth and uniform surface is secur found that a white position comprised of four 'plasterParis. gives very good ed, a white or finbe applied directly We have parts of hme to directly, but suchand in, order to pre finished strengthen it by the coating it is hard wall plaster.

have found very mentitious substance If desired the lime can be replaced directly with neat wall finish and 1 the setting time can be suitably regulated by the addition of plaster of Paris.

In all cases the plaster may be applied according to standard plastering methods without the use of. more force in applying the plaster than is commonly used in apply-' ing such material directly against lath or against the concrete surface. The white and sand finishes can be worked to as thin a coat as is possible both for economy and efliciency. It has been found by thorough tests that a ceiling of this type will resist excessive vibration and heat without any loss of strength and without any falling of the plaster such as occurs under ordinary methods whenever a ceiling is subjected to any amount of vibration or any unusual temperature. Furthermore the bond is not affected by oxidation since it is practically completely protected by the concrete on one side and the plaster on the other, and in the tests which have been made oxidation has never been found to be a source of failure. Test made to determine the absorption of the oil by the concrete also shows no'great deterioration and no failures from this condition. On the other hand efliorescence of various salts on the surface of the concrete prevents the obtaining 'of a good bond between our improved substance and the concrete, and the substanceshould never be applied until the Other forms may be employed embodying the features of our invention instead of the one herein explained, change being made in the form of construction, provided the elements stated by any of the following claims or the equivalent of employed, whether produced by our preferred method or by others embodying steps glqnivalent. to those stated in the 0 ow ngaims.

such stated elementsbe ing at as distinctly claim asour-invent on -1; In a method ofjapplying plaster to a actate I concrete surface; the steps which consist in first coating afset concretesurface with a.

viscous drying oi'l'or varnish capable of dry- 'eed greater than its absorption by the su sequently applied plaster to a 1 ing at aspeed greater than its thickness permitting the forcing thereinto of the sand of a'plaster coat, and then applying such plaster coat before the oil has thoroughly dried. t

2. ,In amethod vof applying laster to a concrete surface, the steps which consist in first coatin a set concrete surface with a viscous vdrying oil or varnishca able of dryahsorption by v the subsequently appliedplas'ter to a thicli IIGSS sand of a plaster coat, and then applying such plaster coat 'beforethe oil has thorpermitting the forcing thereinto of the oughly' dried and forcing the sand of-such "plaster coat into such oil.

3. A composite wall structure consisting 25 of a set concretelayer, azplaster layer, and; an intermediate layer cementing together such concrete and plaster layers, said intermediate layer consisting of a viscous drying oil containing fibrousmaterial.

, 4. A composite wall structure consisting ofaset concrete 1ayer,'a plaster layer, and an intermediate layer of relatively slight thickness cementingtogether such concrete and plaster layers, said intermediate layer consisting of a binder containing a viscous dryingyoi-l capable of drying at aspeed greater than the absorption by'the plaster and the concrete layers of the oil.

V Signed by us, this 13 day of March, 1917.

. Y. SEATON. aroma s. HARRIS. 

